The invention relates to an apparatus suitable for twist-drawing an undrawn or partially drawn yarn. In another aspect, the invention relates to a method suitable for twist-drawing an undrawn or partially drawn yarn.
The use of synthetic yarns presently dominates the textile industry. Although some natural fibers such as cotton and wool are still used today, the majority of yarns used to produce clothing, carpeting, upholstery material and other textile goods are primarily synthetic yarns. In order for synthetic yarns to resemble yarns made from natural fibers, it is necessary to texture or bulk the synthetic yarns. Texturing synthetic yarns in order that such yarns when made into fabrics will have the hand and feel of fabrics made from natural staple yarns is well known in the art. The various texturing processes used to texture synthetic yarns also employ a variety of feed yarns. For example, a feed yarn can be drawn, partially drawn or undrawn and a feed yarn can be twisted or entangled to bind the filaments in the yarn closer together because a yarn that is not twisted or entangled often has filaments that become separated from the yarn that can snag and break during the various processing steps. Also packages of feed yarn should be used in a size or weight best suited for the particular process used. Some of the more commonly employed texturing processes use a feed yarn that has been twisted and drawn. To produce such a feed yarn, a draw-twist machine is frequently used. Such a machine, which is well known in the art, draws an undrawn or partially drawn yarn and then twists the drawn yarn during windup by feeding the yarn to a rotating vertically mounted take-up bobbin through a rotatable "flyer" driven only by the angular momentum of the yarn. Although this type of machine works very well and is widely used, the packages of draw-twisted yarn that can be produced on such machines are relatively small because the windup bobbin itself must be rotated. In some texturing processes where large packages of feed yarn are desirable, it is necessary to splice and recone the draw-twisted yarn to make larger feed yarn packages. An additional problem associated with use of a draw-twisting machine is its relatively slow speed. Most draw-twist equipment operates in the area of 300 to 400 meters/minute and when higher speeds are attempted by using higher drawing speeds and/or draw ratios broken filaments occur.
An object of the invention is to produce large packages of yarn wherein the yarn has been twisted and drawn.
Another object of the invention is to produce drawn and twisted yarn at speeds substantially above 400 meters/minute without producing a yarn with an unacceptable number of broken filaments.
Another object of the invention is an apparatus suitable for producing large packages of yarn wherein the yarn has been twisted and drawn.
Still another object of the invention is an apparatus suitable for producing drawn and twisted yarn at speeds substantially above 400 meters/minute without producing a yarn with an unacceptable number of broken filaments.